docs: def pass_job(db: JobDB, result_queue: Queue, always_cache=False):
      """Create a pull stream that receives jobs and passes them on to the
      database. If the job already has a result, that result is pushed onto
      the `result_queue`.
      """
      @pull
      def pass_job_stream(job_source):
          """Pull stream instance created by `pass_job`."""
          result_sink = result_queue.sink()
  
          for message in job_source():
              if message is EndOfQueue:
                  return
  
              key, job = message
              if always_cache or ('store' in job.hints):
                  status, retrieved_result = db.add_job_to_db(key, job)
  
                  if status == 'retrieved':
                      result_sink.send(retrieved_result)
                      continue
  
                  elif status == 'attached':
                      continue
  
              yield message
  
      return pass_job_stream